Single drive ultrasonic vibration cutting device with three branched chain structure

Abstract

The application discloses a single-excitation ultrasonic vibration cutting device with a three-branch structure. The cutting device comprises at least a fixed column and three column branch chains arranged in parallel with the tool column. Three flexible hinge branch chains are arranged between the fixed column and the three column branch chains. The connecting points of the three flexible hinge branch chains and the fixed column are distributed in the axial direction of the tool column. The ultrasonic vibration cutting device adopts a center column, three flexible hinge branch chains which are uniformly distributed in a circumferential direction at an angle of 120 degrees and have a height difference in a vertical direction, and can generate a three-dimensional tool tip vibration track in space by single input driving. The overall structure is compact and symmetrical, has excellent rigidity, and has no redundant transmission components, so that the problems of synchronous misadjustment and vibration coupling interference of multiple transducers can be avoided.

Description

Technical Field

[0001] This invention relates to a single-excitation ultrasonic vibration cutting device, and more particularly to a single-excitation ultrasonic vibration cutting device with a three-branch structure. Background Technology

[0002] Ultrasonic vibration cutting technology, as a core technology for ultra-precision machining of difficult-to-machine materials, can significantly reduce cutting forces, cutting heat and built-up edge formation due to its pulsed cutting characteristics, effectively improving surface quality and tool life. It is widely used in high-end manufacturing fields such as aerospace, precision molds, and optical components. Currently, the driving methods of ultrasonic vibration cutting devices are mainly divided into two categories: multi-input drive and single-input drive. Among them, the multi-input drive architecture requires 2-3 independent transducers to provide vibration in different directions, which has the disadvantages of large system size, high difficulty in synchronous control, insufficient rigidity, and large energy loss, making it difficult to adapt to high-frequency precision cutting scenarios.

[0003] In existing technologies, tool tip vibration trajectories are mainly divided into three types: one-dimensional, two-dimensional, and three-dimensional. One-dimensional (such as axial and radial) vibration can only achieve pulse cutting in a single direction, which cannot take into account both chip removal and the integrity of the machined surface. It is prone to problems such as uneven cutting texture and high surface roughness, and its applicability is limited to the machining of simple planes or cylindrical surfaces. Although two-dimensional vibration can achieve composite motion in a plane and improve chip morphology, it still has shortcomings such as incomplete coverage of the cutting area and unstable contact between the tool and the workpiece when machining complex curved surfaces, making it difficult to meet the high-precision machining requirements of irregular parts and complex curved surfaces.

[0004] Compared to one-dimensional and two-dimensional trajectories, three-dimensional tool tip vibration trajectories have significant advantages: they can achieve multi-directional pulsed cutting in space, flexibly adapt to the machining of complex curved surfaces and irregular structures, and make the contact angle between the tool and the workpiece and the cutting path more reasonable; they can further reduce cutting resistance, avoid local stress concentration, and reduce workpiece deformation and surface damage; at the same time, they can enhance chip breaking and removal, completely suppress the formation of built-up edge, and significantly improve the surface finish and dimensional accuracy of the machined surface, making them suitable for ultra-precision machining of difficult-to-machine materials such as titanium alloys and ceramics.

[0005] Currently, most devices capable of generating 3D tool tip trajectories rely on multi-input drives or complex coupling mechanisms. Single-input drive solutions are becoming the development trend due to their advantages of simplified structure, convenient control, and high rigidity. However, existing single-input drive devices struggle to stably output accurate 3D trajectories, failing to fully leverage the machining advantages of 3D trajectories. Therefore, there is an urgent need for an ultrasonic vibration cutting device with a single-input drive, simple structure, and the ability to stably generate accurate 3D tool tip trajectories, addressing the pain points of existing technologies and meeting the precision machining needs of high-end manufacturing. Summary of the Invention

[0006] To overcome the above-mentioned defects, the purpose of this invention is to provide a single-excitation ultrasonic vibration cutting device with a three-branch structure that is easy to control, has a simple structure, and has good processing effect.

[0007] To achieve the above objectives, the single-excitation ultrasonic vibration cutting device with a three-branch structure of the present invention includes at least a cutting device; The cutting device includes at least three column branches consisting of a fixed column and a parallel tool column; Three flexible hinged chains are provided between the fixed column and the three column chains; The connection points of the three flexible hinge branches to the fixed column are distributed at intervals along the axial direction of the tool column.

[0008] Furthermore, the three flexible hinge branches are biaxial flexible hinge branches.

[0009] Furthermore, the three flexible hinge branches are evenly arranged at 120° along the circumference of the fixed column.

[0010] Furthermore, the fixed column is provided with countersunk through holes corresponding to the three flexible hinge branches, and the ends of the three flexible hinge branches are provided with cylindrical bosses that cooperate with the countersunk through holes.

[0011] Furthermore, it also includes a fixing device, which includes a vertical plate, a fixed base plate, and a fixing flange; wherein, the fixed base plate is installed horizontally on the ground, the vertical plate is installed vertically at the center of the fixed base plate, and the fixing column is installed vertically on the vertical plate.

[0012] Furthermore, it also includes a drive device, which includes a piezoelectric ceramic transducer and a drive power supply; the piezoelectric ceramic transducer is vertically mounted on a vertical plate via a fixed flange, and the vertical plate and the fixed flange are fixedly connected by fastening bolts and nuts.

[0013] Furthermore, the three biaxial flexible hinge branches have identical structures and dimensions, with the flexible hinge located at the center of the branch and protruding cylindrical bosses at both ends.

[0014] Furthermore, the fixed column is a regular hexagonal prism.

[0015] Furthermore, the top of the column support chain has a cylindrical recessed hole, and the bottom has a cylindrical boss; one end of the flexible hinge support chain is fixed to the fixed column by a fastening bolt, and the other end is fixed to the column support chain by a fastening bolt.

[0016] The ultrasonic vibration cutting device of this invention adopts a central column and a structure of three flexible hinged branches evenly distributed 120° circumferentially with a vertical height difference. It can stably generate a three-dimensional spatial tool tip vibration trajectory based on a single-input drive. The overall structure is compact, symmetrical, and exhibits excellent rigidity, with no redundant transmission components, thus avoiding problems such as synchronization misalignment and vibration coupling interference in multi-transducer drives. Relying on the modal coupling effect formed by the special branch layout, a single-path excitation can decompose into three-dimensional vibration components, avoiding the limitations of conventional single-input devices that can only achieve one-dimensional or two-dimensional vibration. This optimizes cutting forces, reduces cutting heat and cutting force, suppresses built-up edge and burrs, and is suitable for precision machining of difficult-to-machine materials and thin-walled parts. The overall control logic of the device is simple and has good practical value. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the device structure of the present invention (front).

[0018] Figure 2 This is a schematic diagram of the device structure of the present invention (rear).

[0019] Figure 3 This is a structural diagram of a fixed column.

[0020] Figure 4 This is a schematic diagram of a flexible hinge branch.

[0021] Figure 5 This is a schematic diagram of the column support chain.

[0022] Figure 6 This is a structural diagram of a fixed flange.

[0023] Figure 7 This is a structural diagram of a "vertical plate + fixed base plate".

[0024] Drawing number explanation: 1. Carbide insert 2. Tool holder 3. Fixed column 4. Flexible hinge chain 5. Column chain 6. Vertical plate 7. Fixed base plate 8. Piezoelectric ceramic transducer 9. Detailed Implementation

[0025] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0026] In the description of this invention, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0027] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0028] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0029] like Figures 1 to 7 As shown, a single-excitation ultrasonic vibration cutting device with a three-branch structure according to the present invention includes a cutting device, a fixing device, and a driving device.

[0030] The cutting device includes a fixed column, a flexible hinge chain, a column chain, a tool slot, and a carbide insert. The fixing device includes a vertical plate, a fixed base plate, and a fixed flange; the driving device includes a piezoelectric ceramic transducer and a driving power supply. In the overall structure of the device: the fixed base plate is installed horizontally on the ground, the vertical plate is installed vertically at the center of the fixed base plate, and the fixed column is installed vertically on the vertical plate.

[0031] Three dual-axis flexible hinge branches are installed on the fixed column, and a tool holder is vertically installed on the end face of the fixed column, on which a carbide cutting tool is installed.

[0032] The piezoelectric ceramic transducer is vertically mounted on a vertical plate via a fixed flange, and the vertical plate and the fixed flange are fastened together by bolts and nuts.

[0033] The carbide cutting tool 1 is fixed on the tool holder 2, and the tool holder 2 is welded to the center of the fixed column 3.

[0034] The fixed column 3 is a regular hexagonal prism with countersunk through holes of different axial distances around it. The external threaded column at the bottom is coaxially connected to the bolt hole at the top of the piezoelectric ceramic transducer 9.

[0035] The flexible hinge branch 4 is a dual-axis flexible hinge branch; the three dual-axis flexible hinge branches are evenly arranged at 120° along the circumference of the fixed column and are staggered from each other along the axial direction of the column; the three dual-axis flexible hinge branches have the same structure and size, the flexible hinge is located at the center of the branch, and the two ends of the branch are protruding cylindrical bosses, with threaded slots opened at the center of the cylindrical bosses.

[0036] The fixed column has countersunk through holes at corresponding positions for mounting the support chain, which are used to mate with the cylindrical bosses at both ends of the support chain. One end of the dual-axis flexible hinge support chain is installed in the countersunk through hole by a fastening bolt, and the other end is fixed to the upper countersunk through hole of the column support chain 5 by a fastening bolt.

[0037] The column support chain has a cylindrical recess at the top and a cylindrical boss at the bottom. The length of the three column support chains is related to the position of the flexible hinge support chain on the fixed column. The bottom ends of the three column support chains 5 are all fixed to the countersunk through holes at corresponding positions on the vertical plate 6 by fastening bolts.

[0038] The fixed flange 8 consists of two identical semi-circular structures, each with circumferentially distributed through holes. During assembly, the two are placed facing each other and fitted onto the flange of the piezoelectric ceramic transducer 9. The two ends are fixed together with bolts and nuts to form an integral ring. Then, the bolts are tightened and fixed to the vertical plate through the through holes on the semi-circular structure.

[0039] The principle behind generating a three-dimensional motion trajectory at the blade tip in this invention: The fixed column 3 is coaxially arranged with the piezoelectric ceramic transducer 9. The externally threaded post at the bottom of the fixed column 3 mates with the bolt hole at the top of the piezoelectric ceramic transducer 9. Three flexible hinge branches 4 are evenly arranged around the axis of the fixed column 3. The projections of each branch in the axial direction form a 120° angle with each other, and their installation positions in the axial direction are different, forming a stepped staggered distribution. The biaxial flexible hinge in the flexible hinge branch 4 is located at the center. Only the hinge part of the entire hinge can be regarded as a revolute joint, and the rest is regarded as a rigid structure. When the bottom of the fixed column 3 is subjected to the reciprocating excitation of the piezoelectric ceramic transducer 9, if there is no constraint from the three flexible hinge branches, a one-dimensional linear motion will be generated along the axial direction. However, due to the existence of the branch constraints, the actual movement trajectory of the tool tip will be affected by the movement of the branches. Since each branch only rotates through the flexible hinge, only the tangential displacement component perpendicular to the radial direction of the branch can drive the hinge to rotate, while the radial displacement component along the length of the branch cannot trigger the hinge to rotate. Meanwhile, the hinge installation positions of the three sets of branches differ, resulting in a composite posture of "axial main motion + spatial multi-degree-of-freedom micro-amplitude oscillation" for the column, rather than a single linear motion. The final trajectory of the tool tip is composed of the following components: vertical component: the reciprocating motion of the fixed column caused by the input excitation, a one-dimensional trajectory; horizontal component: the tilting motion synthesized by the different rotation angles of the three flexible hinge branches, a two-dimensional trajectory. Since all the above trajectories are generated by the same driving excitation, their trajectories are all simple harmonic functions of the same frequency, but the amplitude and phase are determined by the positions of the branches on the column, the positions of the hinges on the branches, the system stiffness, and the excitation frequency. According to linear vibration theory, the final synthesized trajectory is a three-dimensional Lissajous curve.

[0040] The present invention has been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described above. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention. Many other changes and modifications made without departing from the concept and scope of the present invention should be considered within the scope of protection of the present invention.

[0041] In the description of this specification, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0042] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A single-excitation ultrasonic vibration cutting device with a three-branch structure, characterized in that, It includes at least a cutting device; The cutting device includes at least three column branches consisting of a fixed column and a parallel tool column; Three flexible hinged chains are provided between the fixed column and the three column chains; The connection points of the three flexible hinge branches to the fixed column are distributed at intervals along the axial direction of the tool column.

2. The single-excitation ultrasonic vibration cutting device with a three-branch structure as described in claim 1, characterized in that, The three flexible hinge branches are biaxial flexible hinge branches.

3. The single-excitation ultrasonic vibration cutting device with a three-branch structure as described in claim 1, characterized in that, The three flexible hinge branches are evenly arranged at 120° along the circumference of the fixed column.

4. The single-excitation ultrasonic vibration cutting device with a three-branch structure as described in claim 1, characterized in that, The fixed column is provided with countersunk through holes corresponding to the three flexible hinge branches, and the ends of the three flexible hinge branches are provided with cylindrical bosses that cooperate with the countersunk through holes.

5. The single-excitation ultrasonic vibration cutting device with a three-branch structure as described in claim 1, characterized in that, It also includes a fixing device, which includes a vertical plate, a fixed base plate, and a fixing flange; wherein the fixed base plate is installed horizontally on the ground, the vertical plate is installed vertically at the center of the fixed base plate, and the fixing column is installed vertically on the vertical plate.

6. The single-excitation ultrasonic vibration cutting device with a three-branch structure as described in claim 5, characterized in that, It also includes a drive unit, which includes a piezoelectric ceramic transducer and a drive power supply; the piezoelectric ceramic transducer is vertically mounted on a vertical plate via a fixed flange, and the vertical plate and the fixed flange are fixedly connected by fastening bolts and nuts.

7. The single-excitation ultrasonic vibration cutting device with a three-branch structure as described in claim 2, characterized in that, The three biaxial flexible hinge branches have identical structures and dimensions, with the flexible hinge located at the center of the branch and protruding cylindrical bosses at both ends.

8. The single-excitation ultrasonic vibration cutting device with a three-branch structure as described in claim 1, characterized in that, The fixed column is a regular hexagonal prism.

9. The single-excitation ultrasonic vibration cutting device with a three-branch structure as described in claim 1, characterized in that, The column support chain has a cylindrical recessed hole at the top and a cylindrical protrusion at the bottom; one end of the flexible hinge support chain is fixed to the fixed column by a fastening bolt, and the other end is fixed to the column support chain by a fastening bolt.

Images